[FIX] point_of_sale: Remove the upgrade during the iot build

The iot build fails following the installation of the new
linux-image-6.1.0-rpi8-* packages
The base image is recent enough to skip the upgrade during the build
The "apt upgrade" command is therefore removed from the build

closes odoo/odoo#152828

Signed-off-by: Yaroslav Soroko (yaso) <yaso@odoo.com>

addons/point_of_sale/tools/posbox/overwrite_before_init/etc/init_posbox_image.sh

@@ -19,7 +19,7 @@ echo "export LC_ALL=en_US.UTF-8" >> ~/.bashrc
 locale-gen
 source ~/.bashrc
 
-apt-get update && apt-get -y upgrade
+apt-get update
 
 # At the first start it is necessary to configure a password
 # This will be modified by a unique password on the first start of Odoo